<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图区域 -->
    <el-card>
      <!-- 提示警告区域 -->
       <el-alert title="注意：只允许为第三级分类设置相关参数！" 
                 type="warning" show-icon :closable="false">
       </el-alert>
       <!-- 选择商品分类区域 -->
       <el-row class="cat_opt">
         <el-col>
           <span>选择商品分类：</span>
           <!-- 选择商品分类的级联选择区域 -->
           <el-cascader v-model="selectedCateKeys" expand-triggrt="hover"
              :options="cateList"
              :props="cateProps"
              @change="handleChange">
           </el-cascader>
         </el-col>
       </el-row>
      <!-- tab页签区域 -->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数的面板 -->
        <el-tab-pane label="动态参数" name="many">
          <!-- 添加参数的按钮 -->
          <el-button type="primary" size="mini"
                     :disabled="isBtnDisabled" @click="addDialogVisible=true">添加参数</el-button>
          <!-- 动态参数的表格 -->
          <el-table :data="manyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <!-- 通过作用域插槽接收数据并自定义渲染 -->
              <template slot-scope="scope">
                <!-- 循环渲染tag标签 -->
                <el-tag v-for="(item, i) in scope.row.attr_vals" 
                        :key="i" closable @close="handleClose(i,scope.row)">{{item}}</el-tag>
                <!-- 输入的文本框 -->
                <el-input class="input-new-tag"
                    v-if="scope.row.inputVisible" v-model="scope.row.inputValue"
                    ref="saveTagInput" size="small"
                    @keyup.enter.native="handleInputConfirm(scope.row)"
                    @blur="handleInputConfirm(scope.row)"></el-input>
                  <!-- 添加按钮 -->
                  <el-button v-else class="button-new-tag" size="small" 
                            @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" 
                           size="mini" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" 
                           size="mini"  @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性的面板 -->
        <el-tab-pane label="静态属性" name="only">
          <!-- 添加属性的按钮 -->
          <el-button type="primary" size="mini"
                     :disabled="isBtnDisabled" @click="addDialogVisible=true">添加属性</el-button>
        <!-- 静态属性的表格 -->
        <el-table :data="onlyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <!-- 通过作用域插槽接收数据并自定义渲染 -->
              <template slot-scope="scope">
                <!-- 循环渲染tag标签 -->
                <el-tag v-for="(item, i) in scope.row.attr_vals" 
                        :key="i" closable @close="handleClose(i,scope.row)">{{item}}</el-tag>
                <!-- 输入的文本框 -->
                <el-input class="input-new-tag"
                    v-if="scope.row.inputVisible" v-model="scope.row.inputValue"
                    ref="saveTagInput" size="small"
                    @keyup.enter.native="handleInputConfirm(scope.row)"
                    @blur="handleInputConfirm(scope.row)"></el-input>
                  <!-- 添加按钮 -->
                  <el-button v-else class="button-new-tag" size="small" 
                            @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" 
                           size="mini" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" 
                           size="mini"  @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>
    <!-- 添加参数对话框 -->
    <el-dialog @close="addDialogClosed"
      :title="'添加' + titleText"
      :visible.sync="addDialogVisible"
      width="50%">
      <!-- 添加参数对话框表单区域 -->
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>
    <!-- 修改参数的对话框 -->
    <el-dialog @close="editDialogClosed"
      :title="'修改' + titleText"
      :visible.sync="editDialogVisible"
      width="50%">
      <!-- 添加参数对话框表单区域 -->
      <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  name: 'Params',
  data() {
    return {
      //商品分类列表
      cateList: [],
      //级联选择框的配置对象
      cateProps: {
        value: 'cat_id',
        label: 'cat_name',
        children: 'children'
      },
      //级联选择框双向绑定到的数组
      selectedCateKeys: [],
      //被激活的页签名称(默认第一个)
      activeName: 'many',
      //动态参数的数据
      manyTableData: [],
      //静态属性的数据
      onlyTableData: [],
      //控制添加对话框的显示与隐藏
      addDialogVisible: false,
      //添加参数的表单数据对象
      addForm: {
        attr_name: ''
      },
      //添加表单的验证规则对象
      addFormRules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' }
        ]
      },
      //控制修改对话框的显示与隐藏
      editDialogVisible: false,
      //修改的表单数据对象
      editForm: {},
      //修改表单的验证规则对象
      editFormRules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' }
        ]
      },
    }
  },
  created() {
    this.getCateList()
  },
  computed: {
    //如果按钮被禁用返回true,否则返回false
    isBtnDisabled() {
      if(this.selectedCateKeys.length !== 3){
        return true
      }
      return false
    },
    //当前选中的三级分类id
    cateId() {
      if(this.selectedCateKeys.length === 3){
        return this.selectedCateKeys[2]
      }
      return null
    },
    //动态计算标题文本
    titleText() {
      if(this.activeName === 'many'){
        return '动态参数'
      }
      return '静态属性'
    }
  },
  methods: {
    //获取所有的商品分类列表
    async getCateList() {
      const {data: res} = await this.$http.get('categories')
      if(res.meta.status !== 200){
        return this.$message.error('获取商品分类失败!')
      }
      this.cateList = res.data
      //console.log(this.cateList);
    },
    //级联选择框选中项发生变化会触发次函数
    handleChange() {
      //调用getParamsData函数，拿到每次请求返回的数据
      this.getParamsData()
    },
    //tab页签点击事件的处理函数
    handleTabClick() {
      console.log(this.activeName);
      //调用getParamsData函数，拿到每次请求返回的数据
      this.getParamsData()
    },
    //获取参数的列表数据
    async getParamsData() {
      //证明选中的不是三级分类
     if(this.selectedCateKeys.length !== 3){
       //清空商品分类数据
       this.selectedCateKeys = []
       //将两个表格数据也同步清空
       this.manyTableData = []
       this.onlyTableData = []
       return
     }
     //证明选中的是三级分类
     console.log(this.selectedCateKeys);
     //根据所选分类的id和当前所处面板，获取对应的参数
     const {data: res} = await this.$http.get(`categories/${this.cateId}/attributes`,{
       params: {sel: this.activeName}
      })
       if(res.meta.status !==200){
         return this.$message.error('获取参数列表失败!')
       }
       //console.log(res.data); 
       //将数据循环遍历再用split分割组成一个数组
       res.data.forEach(item => {
         //先判断是否为空，然后用' '切割成数组
         item.attr_vals = item.attr_vals ?
         item.attr_vals.split(' ') : []
         //控制文本框的显示与隐藏
         item.inputVisible = false
         //文本框中输入的值
         item.inputValue = ''
       })
       console.log(res.data);
       
       //判断拿到的到底是动态参数的数据还是静态属性的数据
       if(this.activeName === 'many'){
         this.manyTableData = res.data
       }else{
         this.onlyTableData = res.data
       }
    },
    //监听添加对话框的关闭事件
    addDialogClosed() {
      this.$refs.addFormRef.resetFields()
    },
    //点击按钮，添加参数
    addParams() {
      //预验证
      this.$refs.addFormRef.validate(async valid => {
        if(!valid) return
       const {data: res} = await this.$http.post(`categories/${this.cateId}/attributes`, {
          attr_name: this.addForm.attr_name,
          attr_sel: this.activeName
        })
        if(res.meta.status !==201){
         return this.$message.error('添加参数失败!')
       }
       this.$message.success('添加参数成功!')
       this.addDialogVisible = false
       this.getParamsData()
      })
    },
    //点击编辑按钮展示修改的对话框
    async showEditDialog(attr_id) {
      //查询当前参数的信息
      const {data: res} = await this.$http.get(`categories/${this.cateId}/attributes/${attr_id}`, {
        params: { attr_sel: this.activeName }
      })
      if(res.meta.status !==200){
         return this.$message.error('获取参数信息失败!')
       }
       //请求数据成功就将获取到的信息保存到编辑的表单对象上
       this.editForm = res.data

      this.editDialogVisible = true
    },
    //关闭对话框后重置修改的表单
    editDialogClosed() {
      this.$refs.editFormRef.resetFields()
    },
    //点击按钮修改参数信息
    editParams() {
      //预验证
      this.$refs.editFormRef.validate(async valid => {
        if(!valid) return
       const {data: res} = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`, {
          attr_name: this.editForm.attr_name,
          attr_sel: this.activeName
        })
        if(res.meta.status !==200){
         return this.$message.error('修改参数失败!')
       }
       this.$message.success('修改参数成功!')
       this.editDialogVisible = false
       this.getParamsData()
      })
    },
    //根据id删除对应的参数项
    async removeParams(attr_id) {
      const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning'
      }).catch(err => err)
      //当用户取消了操作
      if(confirmResult !== 'confirm'){
        return this.$message.info('您已取消删除')
      }
      //当用户确认删除操作
      const {data: res} = await this.$http.delete(`categories/${this.cateId}/attributes/${attr_id}`)
      if(res.meta.status !==200){
         return this.$message.error('删除失败!')
       }
       this.$message.success('删除成功!')
       this.getParamsData()
    },
    //文本框失去焦点或按下enter键触发
    handleInputConfirm(row) {
      //trim:去除字符串两端空格
      //判断去除两端空格后长度是否为0
      if(row.inputValue.trim().length ===0){
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      //如果没有return出去，则证明输入的内容有效，需要做后续处理
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false
      //发起请求，保存到数据库中
      this.saveAttrVals(row)
    },
    //将对attr_vals的操作保存到数据库中
    async saveAttrVals(row) {
      const {data: res} = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`,
      {
        attr_name: row.attr_name,
        attr_sel: row.attr_sel,
        //服务器返回的是字符串，我们需要用join在里面用' '拼接成数组
        attr_vals: row.attr_vals.join(' ')
      })
      if(res.meta.status !==200){
         return this.$message.error('修改标签失败!')
       }
       this.$message.success('修改标签成功!')
    },
    //点击按钮显示文输入框
    showInput(row){
      row.inputVisible = true
      //让文本框自动获得焦点
      //$nextTick方法的作用：当页面上元素被重新渲染之后，才会执行回调函数的代码
      this.$nextTick(_ => {
        this.$refs.saveTagInput.$refs.input.focus();
      });
    },
    //删除对应的可选项
    handleClose(i, row) {
      row.attr_vals.splice(i, 1)
      this.saveAttrVals(row)
    }
  }
}
</script>

<style lang="less" scoped>
  .cat_opt {
    margin: 15px 0;
  }
  .el-tag {
    margin: 10px;
  }
  .input-new-tag {
    width: 120px;
  }
</style>